Interphalangeal joints
By : Maab MadianInterphalangeal joints
⦁ Definition
synovial hinge joints extend between the proximal, middle, and distal phalanges of the hand.
⦁ Articular surfaces
1. Head of proximal phalanx
2. Base of middle phalanx
3. Head of middle phalanx
4. Base of distal phalanx
⦁ Ligaments
1. Medial collateral ligament
2. Lateral collateral ligament
⦁ Innervation
Proper palmar digital nerves
⦁ Blood supply
Proper palmar digital arteries
⦁ Movements
Flexion - extension like when you point someone out to come over with your index finger.
⦁ The muscles which share in the flexion of the interphalangeal joints
⦁ Flexor digitorum superficialis
Which flexes the proximal and the middle phalanges of the medial four digits due to its tendon insertions on the shaft of the middle phalanges.
⦁ Flexor digitorum profundus
Which flexes the distal phalanges of the medial four digits due to its tendon insertions on the base of the distal phalanges.
⦁ Flexor pollicis longus
Flexes both of the distal and proximal phalanges of the thumb
Concisely, every finger has three joints while the thumb has two joints.
These joints allow bending and straightening of fingers.
If any two bones get out of their place at the joint, by an external condition as
traumatic injuries of the athletes or falls, the finger becomes dislocated.
.4.1. Dislocated finger Symptoms:
⦁ The finger joint looks crooked or deformed.
⦁ The finger bone appears driven out, such as sticking out to one side.
⦁ Have a swelling and bruising around the joint.
⦁ Have a pain around the joint.
⦁ Finger movement inability.
Note: The common joint to go through dislocation is the proximal interphalangeal joint, which is the middle joint of the finger.
Note
aa4.2. The medical emergency
-
If the doctor suspect that the finger is dislocated by looking
or talking about the symptoms , it is necessary to take
an X-ray to rule out broken or fractured bones
4.3. Reduction
Reduction is the medical term for repositioning the bone into its proper place.
The procedure:
During the procedure, Giving a local anesthesia will numb the pain.
1-Pressing against the bone to liberate it if there’s a still wedged part into the joint.
2- Then pulling the finger outward to get the bone back in its place.
4.4.Splint
Once the bone has been repositioned, its splint is necessary to keep it stable.
Splint prevents the movement and the possibility of finger reinjuring.
Depending on the severity of the injury, the splint must be kept for a few days to a
couple of weeks.
What happen to joints while cracking them?
Synovial fluid is the lubricant-like substance that’s found in-between the joints , It looks as an egg yolk .So while stretching out the joint, there’s a gas releasing ,and this gas forms a bubble and it collapses and pops.
The gas estimates about 20 minutes to return to that fluid and allow the same knuckle to be cracked.
And the heard crackle while standing up quickly ?
The heard sound is the snapping sound which tendons make when they slide between muscles or over bones.
When the joint moves , the tendon snaps over quickly and it makes the popping sound.
Is the knuckle cracking habit safe ?
Cracking the fingers means stretching the joint farther than it normally goes.
By bending the fingers backwards the bones move away from each other , the space
between bones gets bigger , but the amount of synovial fluid stays constant which creates a
low-pressure zone that pulls dissolved gases out of the synovial fluid.
A researcher who chose to pop the joints in one of his hands for 60 years , but not the other hand because he wanted to find out if popping the knuckles would actually cause arthritis?
After 60 years of popping the joints , he found that he didn’t have any more arthritis in one hand than other .
But .. still there is a bad to tell, popping can cause the hand to swell , and weaken the grip.
Reduction is the medical term for repositioning the bone into its proper place.
The procedure:
During the procedure, Giving a local anesthesia will numb the pain.
1-Pressing against the bone to liberate it if there’s a still wedged part into the joint.
2- Then pulling the finger outward to get the bone back in its place.
4.4.Splint
Once the bone has been repositioned, its splint is necessary to keep it stable.
Splint prevents the movement and the possibility of finger reinjuring.
Depending on the severity of the injury, the splint must be kept for a few days to a
couple of weeks.
What happen to joints while cracking them?
Synovial fluid is the lubricant-like substance that’s found in-between the joints , It looks as an egg yolk .So while stretching out the joint, there’s a gas releasing ,and this gas forms a bubble and it collapses and pops.
The gas estimates about 20 minutes to return to that fluid and allow the same knuckle to be cracked.
And the heard crackle while standing up quickly ?
The heard sound is the snapping sound which tendons make when they slide between muscles or over bones.
When the joint moves , the tendon snaps over quickly and it makes the popping sound.
Is the knuckle cracking habit safe ?
Cracking the fingers means stretching the joint farther than it normally goes.
By bending the fingers backwards the bones move away from each other , the space
between bones gets bigger , but the amount of synovial fluid stays constant which creates a
low-pressure zone that pulls dissolved gases out of the synovial fluid.
A researcher who chose to pop the joints in one of his hands for 60 years , but not the other hand because he wanted to find out if popping the knuckles would actually cause arthritis?
After 60 years of popping the joints , he found that he didn’t have any more arthritis in one hand than other .
But .. still there is a bad to tell, popping can cause the hand to swell , and weaken the grip.
References
1.Interphalangeal joints of the hand ; Aaron Beger BSc ; www.kenhub.com ;https://www.kenhub.com/en/library/anatomy/interphalangeal-joints-of-the-hand
2.Identifying and treating a Dislocated Finger;www.healthline.com;
https://www.healthline.com/health/dislocated-finger
3.Clinical Procedures Loukas 1st Edition ; Dislocated Finger Reduction ;
page 136 ; ID 73250 ;https://www.netterimages.com/dislocated-finger-reduction-reduction-of-proximal-interphalangeal-joint-unlabeled-rehabilitation-frank-h-netter-73249.html
4.What’s actually happening when you crack your knuckles ; Megan Thielking ; megan.thielking@vox.com ;https://www.vox.com/2015/2/17/8047879/cracking-knuckles-bad-for-you
5.v4-460px-Stop-Cracking-Your-Knuckles-Step-2-Version-2.jpg.webp ; https://www.google.com/amp/s/www.wikihow.com/Stop-Cracking-Your-Knuckles%3Famp=1
6. Is Cracking Your Knuckles Dangerous To Your Health?? Find out below; Mysterychannel;Operanews; https://ng.opera.news/ng/en/health/26813affc9cb004b24c724f8e919b1e4
7. Dr. Lawrence E. Wineski,PhD;SNELLIS CLINICAL ANATOMY BY REGIONS 10th edition;pp.269,311,423-425,430
8. What You Should Know About Identifying and Treating a Broken Thumb;www.healthline.com;https://www.healthline.com/health/broken-thumb
1.Interphalangeal joints of the hand ; Aaron Beger BSc ; www.kenhub.com ;https://www.kenhub.com/en/library/anatomy/interphalangeal-joints-of-the-hand
2.Identifying and treating a Dislocated Finger;www.healthline.com;
https://www.healthline.com/health/dislocated-finger
3.Clinical Procedures Loukas 1st Edition ; Dislocated Finger Reduction ;
page 136 ; ID 73250 ;https://www.netterimages.com/dislocated-finger-reduction-reduction-of-proximal-interphalangeal-joint-unlabeled-rehabilitation-frank-h-netter-73249.html
4.What’s actually happening when you crack your knuckles ; Megan Thielking ; megan.thielking@vox.com ;https://www.vox.com/2015/2/17/8047879/cracking-knuckles-bad-for-you
5.v4-460px-Stop-Cracking-Your-Knuckles-Step-2-Version-2.jpg.webp ; https://www.google.com/amp/s/www.wikihow.com/Stop-Cracking-Your-Knuckles%3Famp=1
6. Is Cracking Your Knuckles Dangerous To Your Health?? Find out below; Mysterychannel;Operanews; https://ng.opera.news/ng/en/health/26813affc9cb004b24c724f8e919b1e4
7. Dr. Lawrence E. Wineski,PhD;SNELLIS CLINICAL ANATOMY BY REGIONS 10th edition;pp.269,311,423-425,430
8. What You Should Know About Identifying and Treating a Broken Thumb;www.healthline.com;https://www.healthline.com/health/broken-thumb
